PFIT

What is the Physical Function ICU Test (PFIT)?

The Physical Function ICU Test (PFIT) is a specialized assessment tool designed for critically ill patients in the surgical intensive care unit (ICU) (Nordon-Craft et al., 2014). It evaluates physical function outcomes in individuals unable to perform standard exercise assessments, such as the Six-Minute Walk Test (6MWT). The PFIT is particularly useful for patients with acute respiratory failure or ICU-acquired weakness, requiring a tailored approach to assess functional status and recovery potential.

The PFIT consisted of five components: sit-to-stand assistance, shoulder flexion strength, knee extension strength, marching in place, and an upper extremity (UE) endurance task involving arm elevation. However, following a principal component analysis, the test was refined by removing the UE endurance task (Denehy et al., 2013). This modification led to the development of the PFIT-s, a scored version of the test comprising four items.

The PFIT-s provides an ordinal score ranging from 0 to 10, with scores based on the patient’s ability to complete specific tasks. Adjustments are made for patients unable to perform specific components due to illness severity, making it a practical and targeted tool for monitoring physical function in critically ill individuals.

The function ICU test-scored version includes strength assessments for shoulder flexion and knee extension, which provide critical insights into a patient’s muscle functionality. Another component is the evaluation of sit-to-stand assistance, which measures the level of support needed for the patient to transition to a standing position safely. Additionally, marching in place is assessed to objectively measure the patient’s endurance and cardiovascular response during activity.

This safe and inexpensive test has demonstrated utility in predicting hospital discharge outcomes, offering valuable data for clinicians to plan interventions (Denehy et al., 2013). Factors such as chronic health evaluation, ICU length of stay, and comorbidities like sepsis or mechanical ventilation (MV) influence its application, helping to stratify patients into distinct recovery trajectories.

How to use our PFIT template

Carepatron's Physical Function ICU Test template includes the scored version, designed to help you efficiently assess and track the physical function of ICU patients. Follow these steps to get started:

Step 1: Access and use the PFIT template

To get started, click "Use template" within the Carepatron app. This will open the PFIT template, where it is easy for users to fill out patient information, customize sections as needed, and make necessary adjustments before printing or saving the document for future reference.

Step 2: Introduce the test to the patient

Before conducting the PFIT, clearly explain the test to the patient. Let them know it is designed to assess their physical function and outline the steps involved. Ensuring the patient understands the process helps create a comfortable and cooperative testing environment.

Step 3: Discuss and conduct the test process with patient

Guide the patient through each section of the PFIT. Ensure they are positioned correctly, and assist where necessary. Start with strength assessments, then move to sit-to-stand tasks and march in place. Communicate with the patient throughout to maintain comfort and clarity during the test.

Step 4: Gather and interpret results

Once the test components are completed, gather the results and analyze the patient's performance. Focus on the strength scores, sit-to-stand assistance, and endurance data from marching in place. Review these results about the patient's physical condition to interpret their functional status and recovery.

Step 5: Provide patient education and next steps

After interpreting the results, educate the patient on their physical function outcomes and what these scores mean for their recovery. Discuss potential next steps in rehabilitation, including exercise prescriptions and ongoing monitoring, to guide the patient's progress and improve their physical function over time.

Scoring and interpretation

The PFIT is scored based on the patient's performance in four key areas: shoulder strength, knee strength, sit-to-stand assistance, and step cadence (Denehy et al., 2013). Each component is rated on a scale from 0 to 3, with higher scores indicating better physical function. For example, shoulder and knee strength are graded from 0 to 5, while the sit-to-stand test evaluates the required assistance from none to full assistance. The step cadence is calculated based on the number of steps taken per minute, with higher scores reflecting better endurance and cardiovascular function.

The cumulative PFIT score ranges from 0 to 12, categorizing the patient's recovery trajectory. This helps clinicians assess the patient's functional status and make informed decisions regarding rehabilitation intensity and discharge planning. For example, a higher functional status score suggests the patient is more capable of independent mobility and may require less rehabilitation.

Benefits of using this physical function test template

The PFIT template provides a standardized and efficient method for assessing the physical function of critically ill patients in the intensive care unit (ICU). This physical function measure allows healthcare professionals to obtain objective data that reflects a patient's strength, endurance, and overall functional capacity. The template includes assessments for shoulder and knee strength, sit-to-stand assistance, and step cadence, essential for evaluating a patient's recovery trajectory.

Utilizing this physical function outcome measure allows clinicians to implement a pilot exercise training protocol tailored to the patient’s abilities, which can help guide rehabilitation therapy. This is particularly crucial for patients requiring ICU discharge, as it ensures a smoother transition to recovery. Additionally, the PFIT template supports manual muscle strength testing, providing an accurate way to track progress in rehabilitation therapy.

Using the PFIT template allows for identifying the minimal clinically significant difference in physical function, which can be valuable for setting realistic rehabilitation goals. By regularly using functional tests and monitoring functional outcomes, the PFIT template helps clinicians make informed decisions on the intensity and focus of therapy, ultimately leading to better patient outcomes in the ICU and beyond.

References

Denehy, L., de Morton, N. A., Skinner, E. H., Edbrooke, L., Haines, K., Warrillow, S., & Berney, S. (2013). A physical function test for use in the intensive care unit: Validity, responsiveness, and predictive utility of the Physical Function ICU Test (scored). Physical Therapy, 93(12), 1636–1645. https://doi.org/10.2522/ptj.20120310

Nordon-Craft, A., Schenkman, M., Edbrooke, L., Malone, D. J., Moss, M., & Denehy, L. (2014). The Physical Function Intensive Care Test: Implementation in survivors of critical illness. Physical Therapy, 94(10), 1499–1507. https://doi.org/10.2522/ptj.20130451